EFFECTS OF CUTTERHEAD DIAMETER AND LOG INFEED POSITION ON SURFACE QUALITY OF BLACK SPRUCE CANTS PRODUCED BY A CHIPPER-CANTER Svetka Kuljich PhD Candidate E-mail:
[email protected] Roger E. Hernández*† Professor Centre de recherche sur les matériaux renouvelables Département des sciences du bois et de la forêt Université Laval Québec, Canada E-mail:
[email protected] Carl Blais Professor Département de génie des mines, de la métallurgie et des matériaux Faculté des sciences et de génie Université Laval Québec, Canada E-mail:
[email protected] (Received July 2016) Abstract. The effects of the cutterhead diameter and log infeed position on surface quality of black spruce (Picea mariana [Mill] B.S.P.) cants processed by a conical chipper-canter were evaluated. Three cutterhead diameters (345.2, 448.7, and 661.5 mm) combined with three infeed positions or vertical distance from the cutterhead axis to the bedplate on which the log was supported, were studied. The nominal linear cutting speed was fixed at 23.5 m/s. Rotation and feed speeds were adjusted to obtain a nominal feed per knife (chip length) of 25.4 mm. For each cutting condition, two sides of the log were machined at either frozen or unfrozen wood temperatures. Surface quality was analyzed according to waviness and roughness standard parameters. Results showed that surface quality was affected by the cutterhead diameter, infeed position, and wood condition (frozen and unfrozen). Surface quality improved as the vertical distance from the cutterhead axis to the bedplate increased. The global action of the bent knife induced some vibration into the canting edge, which could explain the variation in surface quality among infeed positions.